Much attention has been paid of late to the development of tampons which contain superabsorbent materials, usually polymeric in nature, having a much greater capacity for fluid per unit weight than the cotton and rayon fibers commonly used as the absorbent media in the most popular commerical tampons now being marketed. The increase in fluid capacity and capillary suction pressure exhibited by these superabsorbent materials in such that only minor amounts, i.e. in the range of 5 - 30%, are needed in conjunction with conventional cotton or rayon fibers to provide tampons of vastly improved capacity and better efficiency per unit weight. These improved tampons are therefore capable of being worn for much longer times than prior art tampons. However, one noticeable shortcoming of the higher capacity tampon not experienced with the conventional tampon products was the fact that withdrawal of the used tampon appeared to be more difficult and have greater frictional drag than conventional tampons. This was particularly noticeable when the superabsorbent tampon was removed early and/or when it contained relatively small amounts of absorbed fluid whereby only a portion of the tampon capacity was utilized. In any event, users have reported a perceivable increase in frictional drag during withdrawal of a tampon containing superabsorbent material as compared to their experience with a coventional tampon. This was first attributed in part to the observed greater swelling of the superabsorbent polymer and a resultant increase in bulk. However, no significant reduction in removal resistance was reported when, in an attempt to decrease bulk, the amount of absorbent material present in the tampon was reduced.
Other attempts to solve the problem included: providing a softer, lower density, and less compressed tampon pledget; providing a narrower pledget; isolating the superabsorbent material in the tampon interior; tapering the withdrawal end of the tampon; using smoother wrapper material to reduce friction, including the use of non-absorbent hydrophobic wrappers of the type employed in non-adherent, quick-release surgical dressings; and even adding a surfactant to such wrappers as a lubricant in an attempt to reduce frictional drag.
None of these modifications significantly reduced the incidence of removal difficulty as reported by test panel users.
A basic assumption which guided much of the work in the development of tampons by those skilled in the art was that a more efficient and more comfortable tampon would be one in which a hydrophobic surface is used which remains as dry as possible until the fluid capacity of the tampon core has been reached. Pointed in this direction is a commerically available tampon which contains superabsorbent material in the core, enclosed in a fluid-permeable hydrophobic, spunbonded polyester web. Examination of used tampons indicated a drier surface was acheived but even though the surface web was smooth and of non-adherent character, removal difficulties remained.
Accordingly, it was found to be somewhat contrary to the many previously proposed solutions to the problem when in accordance with this invention, it was discovered that the removal difficulties associated with tampons containing superabsorbent materials can be substantially reduced by providing a wrapper material for the tampon pledget in which the wrapper structure is such that, while it permits ready transmittal of menstrual fluid into the absorbent core of the tampon during use, the wrapper material itself will retain sufficient fluid in its structure to keep the tampon surface soft and lubricated with moisture and thereby reduce the discomfort and difficulties in removal ordinarily associated with tampons containing superabsorbent components.